The invention relates to a circuit for operating a displaceable component in a motor vehicle, in particular a motor vehicle window with at least one motor which is connected to a voltage source by means of an operating switch in conjunction with a relay contact.
In the known circuits of this type, i.e. for the electrical actuation of a motor vehicle window, the relay coil is disposed in a circuit which is closed when the ignition switch is turned on. Thereafter, the window can be opened or closed by actuating the operating switch, while during the time the ignition is turned off the window cannot be operated. This is advantageous in that the windows cannot be opened by children who are not supervised by the driver, but it is disadvantageous in that the driver can actuate the window only after the ignition has been switched on. If one notices, after leaving the car, that one or more windows have not been closed, one must again insert the ignition key and switch on the ignition before the window can be closed. The circuit can be changed in such a manner that the windows can be actuated even when the door is open, by providing a door contact switch which closes the circuit of the relay coil when the door is open. However, the danger exists with such an arrangement that the battery discharges overnight due to the power consumption of the relay coil, if one accidentally forgets to close the door. Furthermore, the relay coil would be constantly energized as long as the ignition is switched on, which very often results in an undesirable heat generation and a high power consumption. Finally the legal regulations in many countries forbids the actuation of the windows after the ignition, has been turned off after opening the driver door or after the opening and reclosing of the driver door.